Solid state image sensing device

ABSTRACT

There is provided a solid-state image sensing device, having: a semiconductor chip having an effective area used for image sensing; a sealing plate provided opposedly to the semiconductor chip; inner leads arranged between an outside portion of the effective area of the semiconductor chip and the sealing plate, and connected electrically to the semiconductor chip; and a sealant in contact with the end portion and the side face on the effective area side of the inner leads.

RELATED APPLICATION DATA

This application is a divisional of U.S. application Ser. No. 08/784,183filed Jan. 15, 1997, now U.S. Pat. No. 6,071,760. The present andforegoing applications claim priority to Japanese application No.P08-784,183 filed Jan. 15, 1996. All of the foregoing applications areincorporated herein by reference to the extent permitted by law.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a solid-state image sensing device, inwhich, in a charge coupled device (CCD) solid-state image sensing devicefor instance, inner leads from a semiconductor chip are formed by meansof tape automated bonding (TAB), and positional dislocation of thesemiconductor chip with respect to a lid is reduced by applying asealant so as to include end portions on the side of an effective areaof the inner leads when a surface of the semiconductor chip is sealedwith the lid.

2. Description of Related Art

Conventionally, in a process of manufacturing a CCD solid-state imagesensing device or the like, a lid is adhered to a chip surface so as toseal the chip surface, thereby to form a CCD solid-state image sensingdevice. With this, in this manufacturing process, a front face of aneffective area used for image sensing by the CCD solid-state imagesensing device is held in the air by a lid, thereby to evade lowering ofsensitivity of the portion in the air caused by the change of arefractive index effectively.

Namely, FIGS. 2A to 2C show sectional views showing a CCD solid-stateimage sensing device in one process of manufacturing a semiconductor,and a chip surface of a semiconductor chip 2 is sealed in a CCDsolid-state image sensing device 1 in this process. Here, thesemiconductor chip 2 is formed in an almost rectangular configuration,an effective area 7 used for image sensing is formed at almost thecenter thereof, and electrodes or the like are formed around thiseffective area. In this semiconductor chip 2, bumps 4 are formed on theelectrodes around thereof in a preliminary process (FIG. 2A), and innerleads 5 by TAB are connected to respective electrodes through thesebumps 4.

A lid 3 is formed of a transparent member such as a glass plate againstthe semiconductor chip 2, and a sealant 6 is applied around theeffective area 7 of the semiconductor chip 2 so that the sealant doesnot penetrate into this effective area and also does not adhere to theinner leads 5. Here, the sealant 6 is formed of half-hardened epoxyresin or the like so that the sealant 6 is not applied to the lid 3 anddoes not flow.

Furthermore, after the lid 3 is placed upon the semiconductor chip 2 insuccession (FIG. 2B) in an atmosphere of inert gas such as nitrogen gas,the sealant 6 is hardened by thermosetting under a state thatpredetermined pressure F is applied, thereby to seal the chip surface ofthe semiconductor chip 2. With this, the CCD solid-state image sensingdevice 1 is shipped through an inspection process or the like.

Now, even when epoxy resin or the like which has been half-hardened sothat it is not applied to the lid 3 and does not flow is applied as thesealant 6, the sealant 6 is lowered in the viscosity and becomes liableto flow at time of thermosetting. Thus, there has been such a problemthat the lid 3 becomes liable to move thus causing positionaldislocation in the case of thermosetting due to lowering of theviscosity of the sealant 6 in a conventional solid-state image sensingdevice 1.

In a CCD solid-state image sensing device, when the lid 3 slips out ofplace at a tolerance or more, the external configuration becomes toexceed a rated value when packaging is made. Further, the sealant 6becomes to swell out to the effective area 7 in keeping with positionaldislocation of the lid 3, the usable effective area 7 is decreased bythat portion and the reliability is also lowered.

SUMMARY OF THE INVENTION

The present invention has been made taking the above-mentioned pointsinto consideration, and is going to propose a solid-state image sensingdevice which is capable of reducing positional dislocation of the lid attime of thermosetting.

In order to solve such subjects, there is provided, according to thepresent invention, a solid-state image sensing device, having: asemiconductor chip having an effective area used for image sensing; asealing plate provided opposedly to the semiconductor chip; inner leadsarranged between an outside portion of the effective area of thesemiconductor chip and the sealing plate, and connected electrically tothe semiconductor chip; and a sealant in contact with the end portionand the side face on the effective area side of the inner leads.

By these means, when a sealant is applied so as to include the endportions of the inner leads on the effective area side of thesemiconductor chip, it is possible to disturb the flow of the sealant bythe inner leads and to prevent the movement of the lid even when theviscosity of the sealant is lowered when the sealant is hardened.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A to 1C show sectional views showing a CCD solid-state imagesensing device according to an embodiment of the present invention;

FIGS. 2A to 2C show sectional views showing a conventional CCDsolid-state image sensing device corresponding to FIGS. 1A to 1C; and

FIG. 3 is a plan view showing a CCD solid-state image sensing deviceaccording to an embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

An embodiment of the present invention will be described in detailhereinafter while referring to the drawings according to circumstances.

FIGS. 1A to 1C show sectional views showing a CCD solid-state imagesensing device according to an embodiment of the present inventionthrough comparison with FIGS. 2A to 2C. In FIG. 1A to 1C, the samestructure as FIGS. 2A to 2C is shown by affixing corresponding referencenumerals, and duplicated description thereof will be omitted.

Namely, in a semiconductor chip 2, inner leads are formed by TAB and alid 11 is adhered thereby to seal a chip surface similarly to aconventional CCD solid-state image sensing device. Here, the lid 11 isformed of a glass plate, and a sealant 12 composed of half-hardenedepoxy resin (i.e., B stage sealer for sealing) is applied in a frameshape. Since the viscosity of the half-hardened epoxy resin is hard tobe lowered, the positional dislocation of the lid 11 is controlled.

At this time, the sealant 12 has been heretofore applied to the outsideso that the sealant 12 bulges out slightly on the effective area 7 sidefrom the end portions of the inner leads 5 on the effective area 7 sidewhen the lid 11 is placed upon the semiconductor chip 2 (FIG. 1A). To beconcrete, the sealant 12 is applied to the lid 11 so as to cover thebumps 4 completely and to bulge out inside by 0.1 [mm] on the effectivearea 7 side from the end portions on the effective area 7 side of theinner leads 5 in internal and external circumference directions, and soas to cross the inner leads 5 completely in the direction along theouter circumference of the semiconductor chip (FIG. 1C). FIG. 3 is aplan view of a solid-state image sensing device after the semiconductorchip 2 is sealed with the lid 3. Corresponding reference numerals areaffixed to those parts that are the same as the parts shown in FIG. 1. Areference numeral 8 represents a polyimide tape.

With this, in the present embodiment, even when the viscosity of thesealant 12 is lowered and the sealant 12 becomes easier to flow, theflow of the sealant 12 is disturbed principally by the resistance fromthe end portions on the effective area side of the inner leads 5 withrespect to the direction of extension of the inner leads 5 andprincipally by the resistance from the sides of the inner leads 5 withrespect to the direction of crossing the inner leads 5.

Then, the lid 11 is housed in an oven after it is placed on thesemiconductor chip 2 and in a state that pressure application F atapproximately 0.2 to 1.0 [Kg] is received, and the sealant 12 isthermo-hardened (FIG. 1B). Besides, this thermosetting is executedwithin the range of 130 to 150 degrees and 1 to 5 hours by means of apreset profile in the present embodiment. With this, the lid 11 isadhered to the semiconductor chip 2 at the sealing width of 0.2 [mm] andthe gap quantity of 0.05 [mm], thereby to seal the chip surface.

With this, the semiconductor chip 2 is formed into a finished productthrough an inspection process after being packaged in a successiveprocess.

In a CCD solid-state image sensing device 10 in the above-mentionedstructure, the lid 11 is adhered to the inner leads 5 by thermosettingof the sealant 12 after the inner leads 5 by TAB are formed on thesemiconductor chip 2 through the bumps 4, thus sealing the chip surface.

At this time, in the CCD solid-state image sensing device 10, thesealant 12 is applied so that the sealant 12 covers the bumps 4completely and bulges out inside from the end portions on the effectivearea 7 side of the inner leads 5 with respect to inner and outercircumferential directions and the sealant 12 crosses the inner leads 5completely with respect to the direction along the outer circumferenceof the semiconductor chip 2, thereby to disturb the flow of the sealant12 principally by the resistance from the end portions on the effectivearea 7 side of the inner leads 5 with respect to the direction of theextension of the inner leads 5 and principally by the resistance fromthe sides of the inner leads 5 with respect to the direction of crossingthe inner leads, thus reducing positional dislocation of the lid 11 attime of thermosetting.

Besides, according to the results of confirmation, it has beencomprehended that it is possible to reduce the positional dislocation ofthe lid 11 which has been approximately ±0.1 [mm] in the case of aconventional application method to approximately ±10 [μm] in the presentembodiment, and to reduce the positional dislocation markedly.

According to the structure described above, by applying the sealant 12so as to cover the bumps 4 completely and to bulge out inside from theend portions on the effective area 7 side of the inner leads 5 withrespect to inner and outer circumferential directions and so as to crossthe inner leads 5 completely with respect to the direction along theouter circumference of the semiconductor chip 2, it is possible todisturb the flow of the sealant 12 by means of the inner leads 5,thereby to reduce positional dislocation of the lid 11 at time ofthermosetting.

Accordingly, it is possible to reduce inferiority of an externalconfiguration thereby to improve yield, it is possible to effectivelyevade reduction of usable effective area by reducing bulging out of thesealant 12 into the effective area, and further, it is also possible toimprove the reliability. Furthermore, it is possible to miniaturize thepackage by the portion that the positional dislocation is reduced.

Besides, in the embodiment described above, a case that the sealant 12is applied so as to cover the bumps 4 completely and to bulge out insidefrom the end portions on the effective area 7 side of the inner leads 5with respect to the inner and outer circumferential directions and so asto cross the inner leads 5 completely with respect to the directionalong the outer circumference of the semiconductor chip 2 has beendescribed, but, the present invention is not limited thereto. In a word,when the sealant is applied so as to include the end portions on theeffective area 7 side of the inner leads 5, it is possible to disturbthe flow of the sealant by the end faces and the side faces of these endportions. Thus, it may also be arranged so that the sealing width isreduced so that the bumps 4 are not covered completely.

Further, in the embodiment described above, a case that the sealant isapplied with thermosetting by being housed in an oven has beendescribed. However, the present invention is not limited thereto, buthardening may be made by column cure, and in this case, hardening can bemade under the condition of 150 to 160 degrees at the sealing surfaceand two to five minutes.

Furthermore, in the embodiment described above, a case thatthermosetting is applied to half-hardened epoxy resin so as to conductsealing has been described. However, the present invention is notlimited thereto, but it can be applied widely to a case of sealing withvarious adhesives such as a case that epoxy resin in a liquid form isapplied with thermosetting so as to conduct sealing, and furthermore, acase that sealing is conducted with adhesives of an ultraviolethardening type.

As described above, according to the present invention, when a lid isadhered to a semiconductor chip in which inner leads are formed by TAB,it is possible to disturb the flow of the sealant with the inner leadsby applying the sealant so as to include the end portions on theeffective area side of the semiconductor chip of the inner leads, thusreducing the positional dislocation of the lid.

What is claimed is:
 1. A solid-state image sensing device, comprising: asemiconductor chip having a surface with an effective imaging area usedfor image sensing; a sealing plate secured to said semiconductor chipover said effective area; inner leads extending between said sealingplate and said semiconductor chip surface and toward said effectiveimaging area, said inner leads having end portions positioned outside ofsaid effective imaging area and between said semiconductor chip surfaceand said sealing plate; and a sealant outside of said effective imagingarea and in contact with and completely surrounding said end portions ofsaid inner leads outside of said effective imaging area thereby sealingsaid inner lead end portions from said effective imaging area, saideffective imaging area being sealant free.
 2. A solid-state imagesensing device according to claim 1, wherein said sealant is epoxyresin.
 3. A solid-state image sensing device according to claim 1,wherein said sealing plate is a glass plate.
 4. A solid-state imagesensing device according to claim 1, wherein said sealant is formed soas to cross between said inner leads.
 5. A solid-state image sensingdevice according to claim 1, wherein said sealant seals between saidsemiconductor chip and said sealing plate.
 6. A solid-state imagesensing device, comprising: a semiconductor chip having a surface withan effective imaging area used for image sensing; a sealing platesecured to said semiconductor chip over said effective area; inner leadsextending between said sealing plate and said semiconductor chip surfaceand toward said effective imaging area, said inner leads positionedoutside of said effective imaging area and between said semiconductorchip surface and said sealing plate; a bump connected to said innerleads; and a sealant outside of said effective imaging area and incontact with side faces and said end portions of said inner leads, saidsealant completely covering said bump and bulging out inside from theeffective imaging area leaving said effective imaging area sealant free.7. A solid-state image sensing device according to claim 6, wherein saidsealant is epoxy resin.
 8. A solid-state image sensing device accordingto claim 6, wherein said sealing plate is a glass plate.
 9. Asolid-state image sensing device according to claim 6, wherein saidsealant is formed so as to cross between said inner leads.
 10. Asolid-state image sensing device according to claim 6, wherein saidsealant seals between said semiconductor chip and said sealing plate.11. A solid-state image sensing device, comprising a semiconductor chiphaving a surface with an effective imaging area used for image sensing,a sealing plate secured to said semiconductor chip over said effectivearea; inner leads extending between said sealing plate and saidsemiconductor chip surface and toward said effective imaging area, saidinner leads having end portions positioned outside of said effectiveimaging area and between said semiconductor chip surface and saidsealing plate, said end portions of said inner leads facing saideffective imaging area; a bump connected to said inner leads; and asealant outside of said effective imaging area and in contact with andsurrounding said end portions of said inner leads, said sealant coveringat least a portion of said bump facing said effective imaging area andbulging out inside from the effective imaging area leaving saideffective imaging area sealant free.
 12. A solid-state image sensingdevice according to claim 11, wherein said sealant is epoxy resin.
 13. Asolid-state image sensing device according to claim 11, wherein saidsealing plate is a glass plate.
 14. A solid-state image sensing deviceaccording to claim 11, wherein said sealant is formed so as to crossbetween said inner leads.
 15. A solid-state image sensing deviceaccording to claim 11, wherein said sealant seals between saidsemiconductor chip and said sealing plate.